Fast food restaurants have remained largely a cash business because credit cards were thought to slow down the payment process.

But new technology has made it possible to speed credit cards through faster than cash, possibly opening up a new profit stream for the fast food restaurant industry.

"When you have the ability to pay by debit or credit and do so at a speed that's faster than paying by cash you make a pretty compelling offer," Whitman said. "Our customers are accustomed to paying by credit and debit card."

Plastic cards, which were once used mostly for big-ticket items, are now being used for the most mundane transactions: paying tolls, buying gasoline and groceries, or reserving movie tickets, often allowing consumers to rack up frequent-flyer miles or promotional bonus points.

Many retailers accepting credit and debit cards have even extended them as a marketing tool by sticking their name and logo on the card, also called co-branded cards.

Whitman said McDonald's currently doesn't plan to launch credit or debit cards with the McDonald's logo on it.

There are more than 31,000 McDonald's restaurants in 119 countries. About 80% of them are run by franchisees.